#include <iostream>
#include <random>

using namespace std;

int main() {
    default_random_engine e;
    normal_distribution<double> dis(0.0, 4.0);
    int total = 1000;
    auto noises = new double[total];
    auto x = new double[total];
    for (int i = 0; i < total; i++) {
        noises[i] = dis(e);
    }
    for (int i = 0; i < total; i++) {
        if (i > 0) {
            x[i] = 0.8 * noises[i - 1] + noises[i];
        } else {
            x[i] = noises[i];
        }
    }
    for (int i = 0; i < total; i++) {
        cout << x[i] << endl;
    }
    return 0;
}
